Very small satellites having a wet mass of between 1 and 10 kg. (2 to 22 lbs.) have been commonly termed “nanosats”. Satellites of this category, which may be as small or smaller than a loaf of bread, are relatively inexpensive to build, but are typically very delicate structures. They may be configured to carry onboard computers adapted to interface with communication systems designed to not only control directional stability including orbit commands, but also to permit deployments of onboard apparatus, such as solar panels and antennae, from their prelaunch stowed positions to their operational positions on an orbiting satellite.
Weight management is critical with respect to design and operation of a nanosat. As such, normal earth-bound structures such as spring-loaded latches and motorized structures to operate such devices, even when miniaturized, may be too massive for consideration for use in a nanosat. Instead, alternatively designed structures are often developed to manage nanosat functions.
For example, the simple operation of remotely uncoupling a solar panel or an array of antennae may require use of electrically controlled structures involving extremely lightweight elements. Achievement of sufficient combinations of strength and lightness can be challenging, particularly when pre-testing protocols may be required to qualify various parts for dependable operability. Indeed, the latter protocols may require that some parts critical to the deployment function may be subjected to several prelaunch cycles to demonstrate satisfactory repeatability, i.e. more than single use functioning without failure, in order to qualify for launch readiness.
One known deployment system used in prior nanosat structures has involved use of thin coiled nichrome wiring configured for melting a nylon fishing line adapted to release or deploy apparatus such as solar panels and antennae. Issues with the coils, including their overheating, fusing, and/or breaking prior to sufficiently heating the nylon to its melting point, as well as lack of system repeatability, have created a need for more reliable deployment structures.
It is therefore desirable to provide improved deployment systems for nanosats.